Constant tension control



Sept. 2, 1952 w, REEVES 2,608,741

CONSTANT TENSION CONTROL Filed June 16, 1950 Y 1 '2 SHEETS-Si-IEET lIII, h... r

k g .Q a m I l [I I r 0 V INVENTOR BY. akl.

ATTOENEPY Sept. 2, 1952 w, REEVES 2,608,741 A CONSTANT TENSION CONTROLFiled June 16, 1950 2' SHEETS-SHEET 2 m [I] I?! FED JNVENTOR.

M41; 7m mums,

Patented Sept. 2, 1952 CONSTANT TENSION CONTROL Walter Reeves,Wakefield, Mass., assignor to Reeves Pulley Company, Columbus, Ind., acorporation of Indiana Application June 16, 1950, Serial No. 168,626

The present invention relates to a constant tension control, and morespecifically to means for controlling the operation of a storage roll orthe like, and a delivery roll associated therewith, under conditionssuch that tension in the material passing between the storage roll andthe delivery roll shall be maintained constant throughout the cycle ofoperation. A primary object of the invention, then, is to providemechanism establishing control over the power delivery to two such rollsof such character as to accomplish such maintenance of uniform tension.

A further object of the invention is to provide means whereby, asmaterial builds up upon, or is removed from, a storage roll in anorganization of the character above suggested, the ratio between theangular velocities of the two rolls will be progressively modified tocompensate for the progressive variation in efiective diameter of thestorage roll. A further object of the invention is to provide meanswhereby, upon completion of a cycle, the starting ratio between suchvelocities may be readily and quickly reestablished without thenecessity of reversing the entire control organization.

, Further objects of the invention will appear as the descriptionproceeds.

1 One embodiment of the present invention finds its primary utility inthe control of a loom beam during the winding of strands thereon; andthe invention has been shown, and will be described, in thatenvironment.

To the accomplishment of the above and related objects, my invention maybe embodied in the form illustrated in the accompanying drawings,attention being called to the fact, however, that thedrawings areillustrative only, and that change may be made in the specificconstruction illustrated and described, so long as the scope of theappended claims is not violated.

Fig. l is a more or less diagrammatic plan view of a control constructedin accordance with my invention'associated with the beam and deliveryroll of such a machine;

Fig. 2 isia fragmentary transverse section taken s bstantially on theline 2, 2 of Fig. 1;

Fig. 3 is a more or less diagrammatic plan view of the control mechanismper se; and

Fig. '4 is a wiring diagram.

Referring more particularly to the drawings, it will be seen that I haveindicated at I a-conventional loom beam with which is conventionallyassociated a, delivery roll II flanked by idlers I2 and I3. ,Inaccordance with conventional practice-,strands or other material It willbe threaded 16 Claims. (Cl. 28-36) V 2 between the idler I2 and aroundthe major periphery of the delivery roll, thence between the deliveryroll and the idler I3, and thence to the beam It, all as indicated inFig. 2. The primary function of the presentinvention is to vary theangular velocity of the beam III, and the ratio of its angular velocityto that of the roll I I, at a rate such as to maintain always a constanttension upon that region of the material l4 between the idler I3 and theeffective periphery of the beam l0. Sincematerial will progressivelybuild up on the beam ID to increase the effective periphery thereof, itwill be obvious that, if the delivery roll II is driven at constantangular velocity, the angular velocity of the beam I0 must beprogressively decreased. A power source, indicated generally by theref-- erence numeral I5, will preferably comprise an electric motor I6with which may, if desired, be associated a speed varying transmissionunit indicated at I I. For the purposes of disclosing the presentinvention, it will be assumed that the unit I1 is operated always at asingle setting. Suitable means, such as a plurality of V-belts- I8,transmit power from the motor I B and unit IT to a pulley I9 fixed to ajack shaft 20 which is mounted for rotation in suitable bearingsparallel with the axes of the delivery roll I I and the beam ID. Asprocket 2| on the shaft 20 is connected by chains 22 to a sprocket 23on a countershaft 24; and power is delivered from said shaft 24. to thedelivery roll II through a sprocket 25, chains 26, and a sprocket 21 onthe shaft II. It will be clear that the shaft II will be driven alwaysat a speed constantly proportional to the speed of the power source I5.v The beam I0 carries a sprocket 28 which is. driven, through chains 29,from a sprocket 30 on the output shaft 3| of a gear unit indicated at32, said gear unit, in turn, being driven by the output shaft 33 (Fig.3) ofa variable speed trans mis-v sion 3 A further sprocket 35 on theshaft 20 is connected by chains 36 to drive the input unit 3I of aslipping clutch indicated generally by the reference numeral38; and theoutput element 39 of the clutch 38 is drivingly mounted upon the inputshaft 40 of the transmission 34. The clutch 38 will be of the type inwhich the element 39 will slip and lag behind the element 31 by aconstant ratio, so long as the torque demand applied thereto remainsconstant. The rateof slip, however, will vary in response to theload'impressed: upon the clutch, in the direction of load variation.

Clutches of the character here under considera the delivery roll I I,

" connections are established. A drum or pulley input shafts 33 and 48upon parallel, spaced cones 4| rotates with the shaft 40, and-acorrespondingly pulley comprising cones 42 rotates with the shaft 33, anedge active belt-43-pro viding a driving connection between saidpulleys.

A lever 44 is operatively connected tcQone-disc of each pulley, throughsuitable thrust bearings, and iaarlever r45 :isoperatively connected tothe othert discaof each pulley, through thrust bearings; said leversibeing-i-ntermediately pivoted :as atrit6iianda4l' so that, as theprojecting ends dfaithegtwo"ilevers iarezmoved towardi'each other, thecones 4| :will *be -moved -tow-ard -each-other to;inclie'ase-thewefiective diameter of the input pulley, rwhile:ithe:.cones 42 will :be --movedaway from-qeach IlllhfikztOrdBClBfi-SB 1'theeffective diameter ot-the output ipulley, thereby increasingthcsspeedaat whichtheshaft :33 will be driven response'to apredetermined speedof rotation of .ishait-zw. .-Means is-provided forcontrolling @the relative-positions of .the levers 44 and-e45,- suchcneans, -in=the illustrated embodimentaiisthe'iinvention, comprising afluid motor and: means or :controlling the same, indicated generally'iby the-"reference numeral 48. Such coht'rol'nneans anayadvantageouslytake the for'miof the idevicetillustrated and described in ioisHarry C.Clay 7 2,306,541 issued Del'zembetzflf); 71942;;the cylinder 49 of*themotor beingsrsecuredi'to" the :lever 45 and .the piston .50 thereofbein'g' secured to the :lever' 44. .Valve mechanism?for'controllingffiuid: flow "to the'motor is indicated at :lfl andimaydnclude anactuating 1ever' -52, .LIn't the illustrated: embodimentof the inventiona bell :crank lever 53 has one arm 55 op'etativlyconnected to the actuator :52 by *a link'f'54, th e other arm 560f saidlever being arranged for actuationby mechanism .lihereinaiterfto' bedescribed.

I -A sprocket 5-1 carried on an extension of the j'ak shaft isconnected, by a chain 58, :to drive a sprocket I59 on =a-shaft fiil ora"difierential' mechanism 6!. A sprocket BZ'on anextension (ifthe-=-input 'sha ft 'l'fl of the 'transmis'sion 34 is connected; {by achain '63, to drive --a sprocket 6'4 on a1secon1d shaft "65 of the unitBl. The unitjlil "may preierably beof the type fully illustrated anddescribed in the patent to William R. Perry ,2,168,07.1.issued August1,1939; As shownIjni FigBjhereof, the shaft 60' is connected'bylalchainlfili to .drive a sun gear 61 loosely mountednon .an..intermediate v.shait 16.9;

the shaft zfi5cis gear connected todrive aisun gear 58 loosely mountedon the shaft 69,; and at carria e- 0; fixed .to .the shaft-$9,. carriesv.a seriesrgof planetarygears H :meshing .with the gearsm EaHdGB. Itwill be clear that thedifferentiallmechanism =willrmeasure any'difierence in welocityxbetween the shafts 20 and-40, and that''iahetshaft ififl w'ill be rotated at :a rate, and in'sia direction,determined by :one-half the ill on the .anmature spindle of the unit 16is operatively associated with a strand 78 con- :nected tothei-levenarm56. Rotation of the drum in- 'one directionrwill shift the lever 53 in acounter-clockwise direction; and the valving mechanism such that suchmovement of the lever '53 will supply fluid to the motor 48 to causesaid motor to move the associated ends of the levers A4 and 45; awayfrom each other. This controlsmechanism .is such that each .position ofthe lever 53 L.will produce. a correspond-, ing: itelativeposition ofthe levers .44 and 45. I

The strand-"1B islcontinuedto the core 19 of. a. solenoidtflThe-relationhetween the solenoid and the lever 53 is suchthatenergizationof the solenoid fiwill ltend to :move the lever 53 in aclockwise direction. In. .some instances, a counter-weight may take theEplace of the'solenoid-.=80-;

=4,. ,I .hav,e indicated the units 15 and 16 and-conventional..eleotricconnections locking togetherthe .armaturesof saidunits, aswitch unitfil lbeingshown, arranged to dominate those electric.connections. -Assuming the connections between .thetwo.selfesyncln'onou's units "to be established, theioperation of the'control, "as thus fardescribed, -.v. ill be. as follows:

.A strand .or strands of material 14 being threaded-past the delivery..roll H and'to the beam 10, in vthe manner illustrated in .Fig. "2,-the ;.motor. I6. willyhe energized to drive the assembly..l'n-the'heg'inning of a cycle, and-assuming theroll t! and the beam1'10 to be of equal'peripheral dimensions, the roll and the beam will bedrivenatequal angular velocities. Upon the completion of its firstirevolution, however, .=.the effective diameter of the beam 10 willbegin to increase .as the material i4 is laid thereon. ..Since ,thetworotors are moving at equal angular velocities, this increase ineffective diameter of the beam 10 will tendlto increase the ;tension .inv,thecstretch of material extending -.-between the delivery .roll .andthe beam. .Ihis increase .in tension will have a braking-effectonthebeam 1.8; and that efiect will be transmitted, through the chain 29and unit -32; to theoutput shaft 33 .of the .transmission-34, .andthence, through the belt 43, to .the input shaft 4810f the transmission.The rate of slip between the parts of ,the clutch 38 will thus-tendtoincrease, .thereby .causingthe shaft 65 pfuthe .difierential unit 5! .to:lag .behind the shaft 60 thereof. The shattGQ will measure that change-in .the .ratesbf "rotation .of the shafts 60 and 65, whereby thearmature of the transmitter :unit il.5--will .be turned. Thearmature ofthereceiver unit 16 will thereby .be turned to a corresponding degree.to windsin on the strand 18 andshift .:the. lever 53 in .acounter-clockwise direction, whereby lthe valving mechanism 5| willcause the motor 48 ,to increase the distance between the ends ofthelevers 44and45, whereby. the ,speedrratio between the shafts 40 and'33 of. the ;tr-an smission :34 willibemodified "to reduce 5, the'velocity'of the shaft lar velocity of the beam I9 will beprogressivelyreduced, at a rate such as 'to'maintain' a constant degree of tensionin'the stretch 'of material extending between the delivery roll IIand-the beam I9.--

It will be clear that, if the organization were used for unwindingmaterial from a storage reel, a tendency toward reduction in the tensioninthe stretch of material-between thestorage roll-andthe delivery rollwould result in a reduction in the rate of slip between the parts of theclutch '38 to produce rotation of the shaft 69 in the oppositedirection, An opposite arrangement of the connection between the unit 16and the motor-49would cause the motor'to be actuated to shift-the'endsof the levers 44 and 45 towardeach other, thereby increasing theangula-r velocity of the shaft 33.

111 the illustrated organization, when the beam I9 has been-filledtodesired capacity, it is desirable to stop further operation of thecontrol while the beam is dofied, and it is highly desirable that thecontrol be returned to startingcondition promptly, so that there may beno delay in preparingto loada new beam. I accomplish such prompt returnthrough'the mechanism now to be-described; v

A main switch82 is arranged to connectthe switching mechanism of Fig. 4into an electric power line. The electric connections between the unitsand I9 are dominated by the switch 82 andcomprise line wires 83 and 84leading from opposite sides of the switch 82. The line wire 83 isconnected to a movable'arm 95 of Q the switch unit 8| said arm 85normally being in contact with a terminal 86 of the self-synchronoussystem connections. A second movable switch arm: 91 is normally incontact'with the opposite terminal 88 of said connections; and a wire 89'connectssaid switch arm 81 with a wire 99, from which a wire 9i leadsto theline wire 84. I A relay, comprising a magnet coil 92 dominatestheswitch arms 85 and 87, being operable, upon energization of said magnetcoil, to" shift the arms 85 and 81 out or contact withithe ter minals(Sand-99. One end of the coil '92 is connected by a wire 93 with thewire 99, and so with the linew'ire'94, while awire 94 leads fromthe'opp'ositeend of saidcoil to a-terminal 95 of a manuallycontrolled,normally open switch. Said switch includes a bridge piece 99movable to-bridge the terminal 95and a terminal 91, the terminal 9'!being connected by a wire 98 with the line wire 83. Obviously, when themanual switch is actuated, to bridge the terminals 95 and 97, the coil:92 will be energized to break the electrical connection between theself-synchronous units I5andl9f ,7

The bridge piece 99.also establishes an energizing circuit for a relayin a switchv unit'9'I', comprising a magnet coil I99. One end of the0011. I99 is connected by a wire 99 with the wire 94, while theother-end of said coil I99 isconnectedby a wire I9I withthe wire 99.Thus, when the terminals 95 and 97 are bridged, an energizing circuitfor said coil I99 is established fromfline wire '83 through wire 98,terminal 9?, bridge piece 96, terminal 95, wire 94, wire99, coil I99,wire I9I, wire 99, and wire 9| to line Wire 84; -.A,switch-arm I92 isdominated by the coil I99-and, uponenergization of said coil, is movedintocontactpwith a terminal I93. .A wire I94 connects said terminal .I93with line wire 93, while-,a wire. I95 vconnects the switch arm i I 92 3.Thereby, the angu 6 with one end of thecoil 1990f the solenoidfifl, theopposite endof said coilbeing connected by wire I91 with line'wire 84.Thuscontactof the switch arm I92 with the terminal I93 -estab-' lishesanenergizing circuit for the solenoid 89 leading from line wire 93throughwire I94,-terminal I93, switch arm I92, wire I95, coil I96,'andwire I91 to line wire 84..

Thus it will be seen that manual shiftingof the bridge piece 99 intoengagement with-the terminals and 9' not-only breaks theelectricconnections through which-the transmitter unit I9dominates the receiverunit I6, but also energizes the solenoid 89 to return the levers and 45to starting position without'at all affecting the unit Si or thetransmitter unit .75. ,J The switch unit 8I includes also a switch armI99 dominated by the relay coil I99 and movable, upon energization ofsaid coil, into contact with a terminal I99; The arm I98 is connected bywire III) with a terminal III normally engaged bya bridge piece IIZwhich engages also, a terminal I I3 connected by wire II 4 with wire 94;The terminal I99 is connected to wire I94., Thus, upon energization ofthe coilv I99, a holding ,circuit for said coil is established, leadingfromgline wire 83through wire I94, terminal I99, switch arm I98, wireII9, terminal III, bridge pieceII2; terminal H9, wirei I4, wire 94, wire99, coil I99, wire I9I, wire 99, and wire 9| to line wire 84. .Whenthelever 44 reaches starting position, it engages the plunger H5 of anormally closed limitswitch IIB, said plunger carrying a bridge pieceIII. A wire H9 leadsfrom the-wire I95 to one terminal of a lamp I I9,the opposite terminal of which is connected by a wire I29 with aterminal I2! of the switch H9, Bridge piece II'I electrically connectsterminals I 2I and I 22, the latter of which is connected by wire I23with line wire 84. Thus, when coil I99 is energized to move switch armI92 into engagement with terminalIIlS, the lamp I99 is energized; and itwill remain energized until plunger H5 is err,- gaged and shifted by arm44 to open switch-I I6.

' A wire I24 connects line wire 83 'withone side of a lampI25, the otherside of which is connected by wire I29 with line wire 84 so that,whenever the switch 82 is .closed, the lamp I25 will be energized. I r

The switch. arm I98 dominates, also, a holding circuit for the coil 92ofthe switchunit- 8I,'said circuitbeing traced from line wire 93 throughwire I94, terminal I99, switch arm I99,'-wire I I9, terminal III, bridgepiece II2, terminal II3';;wire H4, wire 94, coil 92, wire 93, wire 99and wire!!! to line wire 94. After the levers '44 and 45have attainedstarting position, as indicated by :.the deenergization of the lamp H9,and when a new beam has been installed for loading, the operator willpress the button associated with the bridge piece II2 to break theholding circuits for the coils 92 and I99, whereupon the switchpartswill return to the positions in which they are-illustrated, thusbreaking the energizing circuit for the coil I96 and reestablishing thelocking con-. nections between the units I5 and TB.

Pr'eferably, the clutch'38 willbe capable of adjustment while runningto'vary the torque trans= mission capacity of the clutclnthereby varyingthe value of the gross tension maintainedin the stretch of materialbetween the idler I3 and the beam I9; and I have shown-a 'hand wheel 'I21 for efiiecting such adjustment.

Iclaim as my invention: r '1. A constant tension control mechanism com-91' necte'dtcisaia transmission shiftable' 7 element to shiftthe' same,self-compensating ,valve mechanism controlling'fiuid flowto said'fiuidmotor, a transmitter unit of a self-synchronous. system having anarmature. drivingly. connected to said carriage, a receiver unit of a:self -synchronous system having. anx'armature connected to actuatesaidvalvemechanism progressively in one direction, Y upon progressiverotation of saidlreceiver armature in one'di'rection'; electricconnections between saidlunits' to enforce rotation of said receiverarmature in response to rotation of said transmitter armatura'anormally-closed switch the electric connections between said units, re-

lay means operable, upon energization, to move said switch to ope nposition tobreak said connections to "freesaid receiver armature fromthe domination of said transmitter armature, electric motor'meansoperatively connected to said valve mechanism and operable,whensaid receiverarmature is so freed and said electric motor means isenergized, to actuate said valve mechanism in the opposite direction, anenergizing circuit for said electric motor means, a normally open switchin said energizing circuit, relay means operable, upon energization, toclose said normally-open switch, an energizing circuit for said relays,said relays being connected therein in parallel, and a normally-openmanually-operable switch in said last-named energizing circuit.

10. The mechanism of claim 9 including a holding circuit for said relaysindependent of said manually-operable switch, a normally-open switchconnected in said holding circuit, said last-named relay being operable,upon energization, to close said last-named normally-open switch, and anormally-closed manually-operable switch connected in said holdingcircuit.

11. In a device of the class described, a delivery roll and a storageroll, said delivery roll bein driven at a velocity constantlyproportional to the lineal velocity of a strand running between saidrolls, and means for controlling tension inthat reach or" such strandextending between said rolls, comprising speed-varying mean for drivingsaid storage roll including an element shiftable oppositely to varyoppositely the speed at which said storage roll is'driven, and includinga slipping drive connection having a substantially fixed slip ratiounder predetermined load conditions, such ratio being oppositelyvariable in response to opposite load variations, a diiierentialmechanism including a first sun gear, a second sun gear, a planetarygear meshing with said sun gears, and a carriage supporting saidplanetary gear, means driving said first sun gear at a velocityconstantly proportional to that of said delivery roll, means drivingsaid second gun gear through said slipping drive connection at avelocity constantly proportional to the output velocity of said slippingdrive connection, a transmitter unit of a selfsynchronous system havingan armature drivingly connected to said carriage, a receiver unit of aself-synchronous system having an armature operatively connected toshift said element, and electric connections between said unitsenforcing rotation of said receiver armature in response to rotation ofsaid transmitter armature.

12. The device of claim 11 including switch means in said electricconnections operable to break said connections thereby freeing saidreceiver unit armature from the domination of said transmitter unit.

13. In a device of the class described, a delivery roll and a storageroll, said delivery roll being ratio being oppositely variable, inresponse to ope posite load variations, means for measuring thedirection and degree of variationin-suchslip ratio including aself-synchronous receiver and-means for transmitting such variations tosaid receiver to efiect rotation of the receiver armature oppositely inresponsetoopposite variations in such slip ratio, and means .oleratively connecting; aid

armature to shift said element. l4; In a deviceof t-heiclass described,'a e: livery roll and a storage rolLsaid; delivery 011 being driven at avelocity constantly proportional to the lineal velocity of a strandrunning between said rolls, and means for controlling tension in thatreach of such strand extending between said rolls, comprisingspeed-varying means for driving said storage roll including an elementshiftable oppositely to vary oppositely the speed at which said storagerollv is driven, and including a slipping drive connection having asubstantially fixed slip ratio under predetermined load conditions, suchratio being oppositely variable in response to opposite load variations,a differential mechanism including a first sun gear, a second sun gear,a planetary gear meshing with said sun gears, and a carriage supportingsaid planetary gear, means driving said first sun gear at a velocityconstantly proportional to that of said delivery roll, means drivingsaid second sun gear through said slipping drive connection at avelocity constantly proportional to the output vel ci y of said slippidrive connection, a transmitter unit of a self-synchronous system havingan armature drivingly connected to said carriage, a receiver unit of aself-synchronous system having an armature, electric connections betweensaid units enforcing rotation of said receiver armature in response torotation of said transmitter armature, a fluid motor operativelyconnected to said transmission shiftable element to shift the same,self-compensating valve mechanism controlling fluid flow to said fluidmotor, said receiver unit armature being connected to actuate said valvemechanism progressively in one direction, upon progressive rotation ofsaid receiver unit armature in one direction, a normally-closed switchin the electric connections between said units, relay means operable,upon energization, to move said switch to open position to break saidconnections to free said receiver armature from the domination of saidtransmitter armature, electric motor means operatively connected to saidvalve mechanism and operable, when said receiver armature is so freedand said electric motor means is energized, to actuate said valvemechanism in the opposite direction, an energizing circuit for saidelectric motor means, a normally-open switch in said energizing circuit,relay means operable, upon energization, to close said normally-openswitch, an energizing circuit for said relays, said relays beingconnected therein in parallel, and normally-open manually-operableswitch'in said last-named energizing circuit.

15. In a device of the class described, a deliv- 1%1 mfl andas'toragerollg saidideliverwroli'being ans/ ate velocity constantly: proportionalto the lineal vei'ocity of a' strand running-between said rolls, andmeans= for control-ling. tension' in that reach ofsuch' strand extendingbetweentsaid polls; c'ompr-isingspeed'-varying -"means forrdrivmg said;storage-r011 including an' element shift able oppositely tovaryoppositely the speedat which said storageroll is driven, and includingwsii'pping-di iveconnection-having: a substantially fixed sii-izvratiounder predeterminedl'oad: conditions; such-ratio being; oppositelyvariable 1x1 re sponse' to opposite load" variations; means formeasuring; the direction and degree of variation in 'such slip ratioincluding-aself synchronous receiverand" meansfor transmitting suchvaria--- tions to said' reoeiver to efiect rotation ofthe re= ceiver'armature oppositelyin-response to opposite variations in suchslip ratio;a fluid motor-con"- nected 1 to shift-1sai'ck'shift-able element;self-compensating-wave mechanism eontrol-ling -fliiid'fiow motor meansoperativel'y connected: taantuate said valve mechanism; said:switch..meanss eluding means for: energizingzsadckelectricimnml meanswhen, amt only when; said: transmitting means is sozrenderedineffective.

REE RENQES; 21.33.1211:

The" following references M89016 the;

fi Ie'ofth-i'smatenty (l UNL'I'E 511E133 V. Nnmbei Name;

2,392,226: Butter-wort ve1; 8L

